Technical Field
The present disclosure relates to a pitch angle calculation device and an optical axis adjusting device for vehicles.
Background Art
During vehicle traveling, a change in a pitch angle of the vehicle causes a change in an optical axis direction of the headlamp due to acceleration/deceleration and luggage loading. In a method based on conventional art used for solving this problem, a pitch angle is detected and an optical axis direction of the headlamp is adjusted according to the detected pitch angle.
A method of detecting a pitch angle uses, as a basis, information from a vehicle height sensor mounted near a suspension of a wheel. However, this method involves the use of the vehicle height sensor, and causes problems of cost increase and the like.
As a method of detecting a pitch angle without using the vehicle height sensor, JP-A-2013-129284 proposes a pitch angle calculation method. In this method, acceleration in an advancement direction of a vehicle and acceleration in a longitudinal axis direction of a vehicle are detected, and these detected values are applied to a predetermined equation, thereby calculating a pitch angle.